Machine for sewing buttonholes.



No. 740,755. PATE-NTEDOGT 6, 190a F. L. HARMQN.

MACHINE FOR SEWING BUTTONHOLBS.

APPLICATION 1 11.2 NOV; 30. 1896;

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No. 740,755. PATENTED our. 6,1903.

' 'P. L. HARMON.

MACHINE FOR SEWING BUTTONHOLES.

' APPLIUATION FILED NOV. 30, 1 896.

H0 MODEL 15 $HIEETS-SHEET 2.

fv I i No. 740,755. PATENTED OCT; 6, 1 903. P. L. HARMON. MACHINE FOR SEWING BUTTONHOLES. APPLICATION FILED Nov; 30, 1896.

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P. L. HARMON.

MACHINE FOB. SEWING BUTTONHOLES.

APPLIOATION rum NOV. 30. 1896.

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m: uagms vcrzns co. PHoToufHu. WASHINGTON, nsc.

PATENTED new. 6, 1903'.

F. L. HARMON, MAGHINE FOR SEWING BUTTONHOLE5.

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1 Io.'l4(),755 ,PATENTED 00$. 6, 19 03.

F.'L.'HARMON.-

MACHINE FOR SEWING 'BUTTONHOLES.

Arrmm'min rum: NOV. 30, 1898.

no MODEL.

No. 740,755. PATENTED 001*. s, 1903.

F. L. HARMON. MAGHINB FOR SEWING BUTTONHOLBS.

APPLICATION FILED NOV. 30, 1896.

30 MODEL.

15 EHdfiETS-SHEET 8.

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V 'PATENTBD 00T. '6; 1903. F. L. HABMON. MACHINE FOR sswme BUTTONHOLES.

APYLIUATIONLIILIED NOV. 36, 1896.

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PATENTED OCT. 6. 1903.

F.- 1.." HARMON. MACHINE FOR srwim BUTTONHOLES.

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m: nomus PETERS so, Pmrourno PATENTED 001. e, 1903.

F. L. HARMON. v MACHINE FOR SEWING BUTTONHOLES.

APPLICATION FILED NOV. 30, 1896.

' 15 SHEETS-SHEBT 11..

m: norms nms w. FHDYO-Lll'flt}, WASHINGTON, o. a

No. 740,755. I "PATENTED'OGT. 6, 1903. 1213, 'HARMON.

MACHINE FOR SEWING BUT'E'QNHOLES.

APPLICATION FILED NOV. 30, 119.6.

KOIODEL. 16 SHEETS-SHEET 12.

1H: NORRIS M5415. no. P num-u-ruu. wnsmuoma -a No. 740,755. v PATENTED 00$. 6-,.1903.

F,., L. HABMON. MACHINE FUR SEWING BUTTONHOLES.

APPLLIUATION rnmnmov. so, 1896.

no MODEL. I 15 sums-SEEM 1s.

PATENTED OCT. 6, 1903.

I ELL. HARMON. MACHINE FOR SEWING BUTTONHOLES.

APPLIOATIGH FILED NOV. 80, 188B.

15 SHEETS-SHEET 14.

N0 MODEL.

gix v PATENTE-D 0015.6, 1903.

F. L. HARMON. MACHINE FOR SEWING BUTTONHOLES.

no 110mm;

I APPLIUATION FILED Nov. so. 1896 15 SHEETS-SHEET 15.

' uaauuuuuuzwu "UNITED STATES,

rammed October 6, 1903';

5 PATENT OFFICE.

FRANK L. IIARMON, or BEvEnLY, MASSACHUSETTS;

MACHINE FOR SEWIING IBUTTONHOLEQS;

SPECIFICATION forming part of Letters li'atent No. 740,755, dated October 1903;

V v kppllcationfiled November 30, 189 6. $erial No. 613,906. (No model.)

To alt lull/0771 it may concern:

Be it known that I, FRANK L. HARMON, of Beverly, in the county of Essex and Commonwealth of Massachusetts, have invented a new and useful Machine for Making Buttonholes,

all the time between the operations of the,

machine, to be released. to begin the automatic operation of the machine, and a device by which this power may be released, whereupon, said power turns a yoke with stitchforming devices thereon, a half revolution at the beginning of each operation of the machine, and forces a clamp-plate with a pair of clamps thereon, with a material therein, ontof its normal position against the power of a spring,and forces a button-holecutter to cut a button-hole slit in the material, and

forces .the lower members of the clamps.

against a device, and forces said clamps apart, and spreads said button-hole slit, and a chock carried with said clamps is forced between said clamps to keep said clamps apart to keep the button-hole slit spread, and forces devices to generate and store power in a device called a lender to be released to cause,

the stitch-forming devices to cease sewing after a buttonhole slit is sewed, and forces devices to control and employ another power connected with the driving pulley of the machine, to start and drive mechanisms, whereupon, the sewing and the generating and storing of power is accomplished, and causes said power to force a device to release the power in store in the device called ahuffer, whereupon, the power operating the mechanisms, whereupon, the sewing and the generating and storing of power is accomplished, automatically ceases operating said mechanisms, and a'device is operated to instantly cause these mechanisms to cease operating, leaving controlling power in store, to be released to cause the machine to perform another operation.

I believe that I am the first to devise devices adapted to be forced by stored power released to move a material, whereupon, a

button-hole slit is cut and spread; and that n a machine in the operation of which two dis tinct powers must be employed, one power containing main power, devices to be operated by controlling power, whereupon, the main power may be automatically controlled, em played and disem ployed, operative devices to be operated by the main power, a device,

whereupomcontrolling power may be released by an outside agency, or otherwise, where- ,upon, the entire automatic action of the apparatus may be automatically controlled as follows: the action of the apparatus begun, the main power controlled and employed, the length of the time that the automatic action continues, controlled, the number of movements of the operative devices controlled,

the amount of controlling power generated, controlled, the main power again controlled and disemploy'ed, leaving a'proper amount of controlling power in store.

This specification also discloses a clamp plate and novel mechanism, whereupon, the clamp-plate is moved little by little longitudinally and is swung little by little diagonally of a button-hole slit in a material held by a pair of clamps movably mounted upon said clamp-plate, and novel devices, whereupon, a yoke is turned little by little carrying the stitch-forming devices little by little in a circular direction around the end of abnttonhole while the machine is sewing.

A particular stitch is formed as follows: a

loop of an upper thread above a material to. 4

be sewed is carried down through the solid material near to the button-hole slit out therein, and a loop of an under thread beneath the material is carried through the loop of the upper thread beneath the material and up through the material or button-hole slit, and a loop of the upper thread is carried down are vibrated, and novel mechanism, whereupon, said needles andilooper are vibrated as aforesaid, in lines as aforesaid.

I believe that I am the first to vibrate two straight needles in straight lines across each other in the forming of this stitch expressly to engage loops of two threads by said needles above the material, and to avoid using a looper above the material, and to vibrate a looper across the straight lines in which said needles are vibrated beneath the material in the forming of this stitch expressly to engage the upper and under threads beneath the material while forming this stitch, and to vibrate the under needle in a straight line expressly to avoid damaging the under needle while passing it through a tough material inthe forming of this stitch; and as the novel function of this combination comprises the thrusting of a straight under needle from beneath the material up through the material as described in the forming of this stitch, and

across the straight line in which the upper needle is vibrated above the material, and the engaging of loops by said needles, and as the result of the combination is the particular stitch formed of loops of two threads as described, the novelty of the combination must reside in the novel mechanism, whereupon, said needles and looper are vibrated as aforesaid to obtain said novel functions.

Therefore, I believe that the com bination of any two straight needles vibrated in straight lines as aforesaid, and any looper vibrated as aforesaid, whereupon, loops of two threads are engaged as aforesaid to avoid the use of more than one looper, and to avoid the damaging of the under needle while passing it through the material to form this particular stitch is of my invention.

The above-named new and useful characteristics, together with other new and useful characteristics of this invention will hereinafter appear, and will be fully shown in the accompanyingdrawings; and will be fully described hereinafter, and will be claimed in the claims appended hereto by claiming devices operated as the devices shown and described.

Fig. 1 is a side elevation of the machine which is the subject of this invention, with the stand, and bed-plate shown as if a part of each were broken away. Fig. 2 is a top plan of the same with the work-table, or stationary support, which supports a device for cutting a button-hole slit, and the clamp-plate which supports a pair of clamps, removed. Fig. 3 is a bottom plan of this machine. Fig. 4 is a longitudinal section of the same. Fig. 5 is a cross section on line 5 5 of Fig. 2. Fig. 6 is a perspective detail showing the feed-lever, and striker-lever, and the parts carried with them. Figs. 7, 8 and 9 are perspective details illustrating some of the detached parts described as follows: Fig.7 shows acam-disk, comprising three cam-faces and a ratchet. Fig. 8 illustrates the support for said camdisk to rotate upon, and also shows the feedlever and striker-lever on said support. Fig. 9 illustrates a collar to hold said cam-disk on said support. Figs. 10, 11, 12 and 13 illustrate two sets of pawls one set of which is used as a detent. Fig. 14: is a detail illustrating a device for retaining power in store hereinafter termed controlling power, because it controls the entire automatic action of the machine upon the material after it is released. Fig. 15 illustrates mechanism, whereupon, a yoke with stitch-forming devices mounted upon it is turned, and also illustrates devices, whereupon, a clamp-plate is moved sidewise. Fig. 16 shows a cross section of adjustable devices, whereupon, the clamp-plate may be caused to move sidewise at a greater or less distance so that the width of a button-hole may be changed without manually adjusting the needle toward or from a button-hole slit. Fig. 17 illustrates a part of a mechanism, hereinafter described and termed a stop-fork, whereupon, power in or connected with a clutch mechanism is automatically controlled aud employed. Figs. 18, 19, 20, 21, 22 and 23 illustrate a clutch mechanism. Fig. 24illustratesa part of the yoke and devices carried with the yoke, and devices,whereupon, controlling power is held in store in a powerful main-springina mechanism hereinafter termed an auxiliary mechanism to be released to control the entire automatic operation of the machine. Fig. 25 illustrates the yoke, which comprises two journals rigidly held in alinement and in relative positions with each other. Fig. 26 shows the upper needle-bar bearing with the needlebar connected therewith. Fig. 27 shows the under needle-bar bearing with the'needle-bar and looper-carrier connected therewith. Fig. 28 illustrates a throat-plate, or button. Figs. 29, 30, 31, 32 and 33 illustrate a bufier. Fig. 34 isa plan of the top of said work-table, or stationary support, with a cutter-lever supported upon it. Fig. 34 is a detail illustrating a metal clamp, or adjustable socket in which a raw-hide cutter-block is shown. Fig. 35 is a top plan of a clampplate, with a pair of clamps movably connected therewith. Fig. 35 is a sectional detail in elevation from Fig. 36 to show the c'utter in operative position with said raw-hide cutter-block, and to show that said adjustable socket, in which the raw-hide cutter-block is confined is fastened to said work-table, or stationary support. Fig. 36 shows a section of Fig. 35 on line 36 36, mounted upon a longitudinal sec tion of Fig. 34. Fig. 37 shows a part of said chinery on the under side of it to view. The

yoke in position with a cross section of Fig. l 34, and a cross section of the devices shown in Fig. 36 on line 37 37 of Fig. 36 mounted upon said cross section of Fig. 34. By these views being so described the assembling of the devices shown in the several views is illustrated. Fig. 37 shows a section of said yoke to illustrate a device for moving the clamp plate and clamps between thecutter-block and cutter. Figs. 38, 39, 40 and 41 illustrate two straight needles that are vibrated in straight lines across each other, and a looper that is vibrated across the straight lines in which said straight needles are vibrated. Fig. 38 shows a top view of a piece as broken out of the work-table, or stationary support, to show how a movable device, whereupon, a button-hole slit is spread, is movably connected with the work-table, or stationary support. Fig. 39 shows a section of Fig. 38 on line at a of said figure, to show more fully how said movable device is movably connected with said work-table, or stationary support. Fig. 42 illustrates the stitch formed with two threads. Figs. 43, 44, 45 and 46 illustrate two straight needles and a looper which are vibrated in the same lines as the other needles and looper are vibrated, but form a stitch with three threads. Fig.4? illustrates the stitch formed with three threads by these needles and looper. Figs. 48, 49 and 50 show a modification of the machine in which my invention is embodied showing that other mechanisms and forces maybe employed together without departing from the novel scheme disclosed by this invention, whereupon, one power is automatically generated and stored, and another power is automatically controlled, employed aud disemployed on account of the stored power being released. Fig. 51 illustrates the mountingof the pin a Figs. 1, 2, 3 and 4 disclose the fact that the bed-plate W is pivoted to the stand W by the pivots WV so that the bed-plate maybe turned up, on its pivots, to expose the mawork-table, or stationary support A is supported upon the brackets a and ct fast to the bed-plate WV so as to admit of the turning of the yoke B one hundred and eighty degrees from the position in which it is shown in the drawings, under and around the end of the work-table, or stationary support A as will be plain by Figs. 1 and 2. Fig. 2 shows a plan of the machine with the exception of the work-table, or stationary support, and the cl amp-plate, which are removed. The worktable, or stationary support A is shown in Fig. 34, and is replaced in position on Fig. 2 by'putting the slot or slideway A, shown in said work-table over the block 01, shown in Fig. 2, and is secured to the brackets a and a by screws so that the block d may be moved longitudinally-in said slot. The clampplate D is shown in Fig. 35, and is placed upon the work-table, or stationary support A by placing the long slot D, shown in said clamp-plate, over the block, or adjustable device'm shown in Figs. 2 and 15, and placing the pivotal stud, or pin (1' shown secured in said clamp-plate into the hole 'dlin the block (1, thereby forming the movable axis, shown in Fig. 36. It will be observed that by this construction the movable axis and clampplate may be moved longitudinally of the machine by moving the block at longitudinally in the slot A in said work-table.

Attention is called to the fact that the clamp-plate D is shown toward the left in Fig. 4, as far as it is ever carried intermittently by the feeding mechanism; but before" the sewing is begun in every operation of the machine,the block (1', movable axis, clam p-plate, clamps and material held thereby, are thrust longitudinally of the machine by a mechanism hereinafter described, out of the position in which they are shown in the drawings in the direction which is toward the left in Fig. 4, thereby sliding the clamp-plate D upon'the work-table, or stationary support and guiding said clamp-plate longitudinally by said adjustable device, or block m in the long slot D in said clamp-plate; and the material held by said clamps is thereby carried under the cutter I-I so that a button-hole slit may be cut in said material; and said movable axis, clamp-plate, clamps and material held thereby, are instantly returned to their original position, or into the position shown in Fig. 4, onaccount of said mechanism.

The cam-dlsk,shown in Figs. 7 and 2, comprising three cam-faces, viz: K, M, and k is shown rotatably mounted upon the vertical hearing, or support, shown in Fig. 8, in the manner shown in Fig. 4; and the support m is shown rigidly secured in the bracket 0:, in Figs. 2 and 15. In Fig. 15 the stud m is shown movably secured in the support m Upon said stud m the lever m is rigidly secured; and upon said lever M the roll al is movably secured. Upon the upper end of the stud m the lever m is rigidly secured; and upon the lever m the above described block, or adjustable device m over which the long slot D in the clamp-plate D is placed, as above described, is adjustably secured, as, and for the purpose hereinafter described. To the lever m, and the bracket a, the spring m is secured; and the force of said spring holds the roll 01 against the cam face M, which prevents the block, or adjustable device m and the clamp-plate connected therewith from being easily moved laterallyas will be plain by Fig. 2.

\Vhile the roll (1 is 1h us held against the part of the cam-face M which is concentric with the center of the cam-disk, and the camdisk, shown in Figs. 7, 2 and 4 is being moved IIO little by little in a circular direction by devices hereinafter described, the cam -face K allows the roll d upon the studd shown in Fig. 4, the slide d fast to said stud and in the slideway (1", shown also in Fig. 2, the block (1 fast to said stud, the pin, or pivotal stud cl, pivoted in said block d forming said movable axis, the clamp-plate D fast to said pin, or pivotal stud d, the clamps on said clamp-plate and the material held by said clamps, to be moved little by little by the force of the spring (Z connected with the stud (Z and a device onsthe slideway (1, shown also in Fig. 2, toward the right in Fig. 4, therebysliding the clamp-platelongitudinally upon the work-table, or stationary support and guiding said clamp-plate longitudinally of a button-hole slit in a material held in the clamps by said adjustable device, or block in while one straight side of a button-hole slit is being sewed.

While one angular part of a button-hole slitis bei ngsewed, the clamp-plate D is swung on its movable axis by the block, or adjustable device "In in the long slot D in the clam pplate, against the stress of the spring m shown in Fig. 15, little by little, diagonally of a button-hole slit, on account of a part of the cam-face M, shown in Fig. 15, which is eccentric to the center of the cam-disk, being moved little by little against the roll d shown in Fig. 15, moving said roll and the block, or adjustable device m shown in Figs. 2 and 15, which is in said long slot D in said clamp-plate as above described, diagonally in one direction through the connecting devices, shown in Fig. 15 between-the roll d and the clamp-plate D, thereby carrying the clamps bysaid clamp-plate, and moving the device 01, inovably secured to the work-support A, as shown in Figs. 34, 38 and 39, with said clamp-plate while said movable axis is being moved little by littleas aforesaid longitudinally; and said cam-face M allows the spring m shown in Fig. 15, to move said connecting devices, clamp-plate, said clamps, and said device a as aforesaid in the opposite direction While the other angular part of the button-hole slit is being sewed.

While the curved parts of a button-hole slit are being sewed, said devices move the clampplate little by little, longitudinally, and swing the clamp-plate little by little diagonally, while the stitch-forming devices are rotated and vibrated about the curved parts of a button-hole slit,thereby carrying the clamps with said clamp-plate, and the material with said clamps.

The above described mechanism, shown in Figs. 15 and 2, between the cam-faceM and the clamp-plate D, including the roll (Z and the block, or adjustable device m is termed a connecting device in the claims appended hereto; and the above described mechanism between the cam-face K and the clamp-plate D, including the roll 01 the block d, and the pin, or pivotal stud d, is also termed a connecting device in the claims appended hereto.

It is understood that the above described cam-disk comprising said cam-faces K and M rotatably mounted upon the vertical bearing, or support, and turned little by little, by suitable devices hereinafter described, together with the clamp-plate D and said connecting devices, whereupon, said clamp-plate D with the clamps thereon is moved as aforesaid, whereupon, a button-hole slit is sewed, and stitches are formed in straight angular and curved lines form one of the principal novel combinations of this invention, and it is claimed in the claims appended hereto.

Fig. 16 shows how the block, or adjustable devicem may be man ually adjusted or moved on said lever m, and secured in another position on said lover. The nut m is threaded upon the screw shown in Fig. 16, and is fitted loosely into the groove in said lever m. By tightening the screw shown in the block, or adjustable device m the lever m is clamped or gripped between said nut m and the shoulder of said screw. The block, or adjustable device m will then easily turn on the body of said screw, while said screw is thusheld rigidly from slipping outof its position on said lever m. On accountof these devices, shown in Fig. 16, whereupon, said block, or adjustable device m is adjustably secured on said lever m, the clamp-plate D may be caused to automatically swing diagonally, more, or less, upon its movable aXis, thereby carrying the clamps and the material held thereby diagonally a greater or less distance, whereupon, the width of a buttonhole can be changed.

The mechanism, whereupon, said cam-disk is turned little by little, upon its vertical support, or hearing, whereupon, the clamp-plate, clamps and material are moved as above described, is described as follows:

The striker-lever k and the feed-lever 7c, which carries the pawl-carrier m with its pawls 7c, are shown in Fig. 6. In Fig. 8 these levers are shown on their support m To assemble these parts of the machine, the camdisk, shown in Fig. 7, comprising three cam faces, viz: K, M, and 7a and the ratchet J, is placed upon the support m so that the ratchet J is connected with the pawls k, and so that thecain-face is placed in contact with the stud 70 Then the collar, shown in Fig. 9 is placed upon the support m to hold said devices upon said support; and the screws shown in said collar are inserted into the groove m in the support m The support m is then made fast to the under side of the bed-plate W, as is shown in Fig. 3. The lower journal I), of the yoke B, shown in Fig.

' 25, is placed in the hole or journal bearing in the support m and the journal I) is placed into the journal bearing in the end of the arm W The pawls of the pawl device an, shown in Fig. 13, are used as detents to prevent backward movement of said cam-disk and the yoke B, as will be plain by Fig. 3. The pawl device m in which the pawls k operate as detents, is made fast to the bed-plate W by screws, as will also be plain by Fig. 3.

The connecting devices shown in Figs. 1, 3 and 6, between the main shaft and said striker-lever, whereupon, said striker-lever v 10 and is described in the description of the is vibrated, are described as follows: The screw 11 is carried by the hub 19 shown in Fig. 1. The block is carried by said screw. The lever k is rocked upon its fulcrum 19 by the block carried in the slot in the lever 10. The lower end of the lever k is movably secured to the rod k and the rod 70 is carried back and forth by said lever is". The other end of said rod 79 is movably secured to the striker-lever k and by the rod the strikerlever k is oscillated on its bearing hi Attention is called to these devices in Fig. 3 also, to show how the rod 10 is movably secured to the striker-lever 11: and attention is also called to Fig. 8 to show how the striker lever is? is movably mounted upon its vertical support, or bearing m The feed-screw is, shown in Figs. 1, 3 and 6, is secured to, and carried by said striker-lever 75 and is forced against the block 10 which block is movably secured upon said feed-lever k, and the feed-lever 76' with the pawl-carrier fast thereto is moved; and the pawls in said pawlcarrier engage said ratchet, which is a part of said cam-disk, shown in Figs. 1,3, 4 and 7, and said cam-disk is thereby moved on its vertical bearing, or support m shown in Figs. 8 and 4. The spring B is secured to the other end of the feed-lever 70', and is also secured to a hook in the bed-plate of themachine, as will be clear by Fig. 3. When the feed-screw k carried by the striker-lever k strikes the block 75 which is movably secured to the feed-lever k, and moves said feed-lever,the spring 13* is thereby expanded; and when the striker-lever k is moved back in the opposite direction, the spring 13, secured to the other end of said feed-lever it, pulls the lever it back to its original position, and said feed-lever is stopped in its original position, by the stop screw it, shown in Figs. 3 and 6, carried by said feedlever, being brought into contact with the edge of the bracket m by said feed-lever, which will also be plain by Figs. 3 and 6.

By Figs. 1 and 3, it will be seen that the point of the feed-screw k carried by the striker-lever k is at a distance from the block 70 which is movably secured to the feed-lever 7c. The space between the point of the feed-screw k, which is movably secured to the striker-lever k is traversed by said screw before movement is given thereby to the feed-lever. Thus it will be seen that the stroke of the striker-lever k is longer than the stroke of the feed-lever it while the straight side and angular part ofa buttonhole slit are being sewed. By Figs. 1 and 8, it will be seen that the block M, which is movably secured on the feed-lever 7c, is held in position by the spring 71;, which is secured to the pin in said block, and also to the pin in said feed-lever; and it will be remembered that the stud 7e shown in Figs. 1 and 8, is shown in Fig. 3 in contact with the cam-face assembling of parts of the feeding mechanface k in Fig. 3 is such that the block 10 upon the feed-lever must be forced inward toward the center of said cam-disk, by the cam-face acting upon the stud 7e shown in the dotted lines in the block, and shown also in Fig. 8. The device m shown in Figs. 4 and 7 is a friction band to prevent overthrow of the cam-disk.

Attention is called to the circular stitchbar 26 which is adjustably secured to the block 143 which block is hereinabove described as being moved inward upon said feed-lever toward the center of rotation of said cam-disk at this time, by said cam-face 75 thereby expanding the spring 70 secured to the pin in said block it", and to the pin in said feed-lever 10. As said circular stitch-bar is thus carried inward, it is brought nearer to the inclined block 70 secured to the striker-lever, thereby partially taking up the space between said circular stitch-bar and the inclined block 0 on said striker-lever 0 and immediately the stroke of the feed-lever, which is less than the stroke of the strikerlever, is thereby automatically lengthened to, or nearly to, the stroke of the striker-lever. On account of these devices, the speed of the clamp-plate with the clamps thereon, is antoinatically changed to a proper speed to cooperate properly with the stitch-forming devices so that the proper number of stitches v are made in the eye of a button-hole. After the circular part of the eye of the button-hole slit is sewed, said moving cam-face k allows the spring 70 to move the block 10 on said feed-lever k back to its original-position and away from said inclined part of the block 7t", secured to the striker-lever Zea-whereupon, the long stroke of the feed-lever is automatically chan ed back to its original or short stroke, so that the proper number of stitches are made in the angular part and the' other straight side of the button-hole slit. It will be observed that adjusting the feed-screw 10 shown in Figs. 1, 3 and 6 by hand, causes the number of stitches in the sides of a button-hole slit to be changed; and adjusting the circular stitch-bar by hand, causes the number of stitches in the eye of a button-hole slit to be changed. A

Movabl y secured to the clam p-plate D,shown' in Figs. 35, 36 and 37, is a pair of clamps, described as follows: The lower clamp-members 'r' and r are movably mounted upon said 

